/* Copyright (c) 2002, 2010, Oracle and/or its affiliates. All rights reserved.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; version 2 of the License.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software Foundation,
   51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA */

/*
  Functions to read and parse geometrical data.
  NOTE: These functions assumes that the string is end \0 terminated!
*/

#include "sql_priv.h"
#include "gstream.h"
#include "m_string.h"                           // LEX_STRING

enum Gis_read_stream::enum_tok_types Gis_read_stream::get_next_toc_type()
{
    skip_space();

    if (m_cur >= m_limit)
        return eostream;

    if (my_isvar_start(&my_charset_bin, *m_cur))
        return word;

    if ((*m_cur >= '0' && *m_cur <= '9') || *m_cur == '-' || *m_cur == '+')
        return numeric;

    if (*m_cur == '(')
        return l_bra;

    if (*m_cur == ')')
        return r_bra;

    if (*m_cur == ',')
        return comma;

    return unknown;
}


bool Gis_read_stream::get_next_word(LEX_STRING *res)
{
    skip_space();
    res->str = (char *) m_cur;

    /* The following will also test for \0 */
    if ((m_cur >= m_limit) || !my_isvar_start(&my_charset_bin, *m_cur))
        return 1;

    /*
      We can't combine the following increment with my_isvar() because
      my_isvar() is a macro that would cause side effects
    */
    m_cur++;

    while ((m_cur < m_limit) && my_isvar(&my_charset_bin, *m_cur))
        m_cur++;

    res->length = (uint32) (m_cur - res->str);
    return 0;
}


/*
  Read a floating point number

  NOTE: Number must start with a digit or sign. It can't start with a decimal
  point
*/

bool Gis_read_stream::get_next_number(double *d)
{
    char *endptr;
    int err;
    skip_space();

    if ((m_cur >= m_limit) ||
            ((*m_cur < '0' || *m_cur > '9') && *m_cur != '-' && *m_cur != '+')) {
        set_error_msg("Numeric constant expected");
        return 1;
    }

    *d = my_strntod(m_charset, (char *)m_cur,
                    (uint) (m_limit - m_cur), &endptr, &err);

    if (err)
        return 1;

    if (endptr)
        m_cur = endptr;

    return 0;
}


bool Gis_read_stream::check_next_symbol(char symbol)
{
    skip_space();

    if ((m_cur >= m_limit) || (*m_cur != symbol)) {
        char buff[32];
        strmov(buff, "'?' expected");
        buff[2] = symbol;
        set_error_msg(buff);
        return 1;
    }

    m_cur++;
    return 0;
}


/*
  Remember error message.
*/

void Gis_read_stream::set_error_msg(const char *msg)
{
    size_t len = strlen(msg);			// ok in this context
    m_err_msg = (char *) my_realloc(m_err_msg, (uint) len + 1, MYF(MY_ALLOW_ZERO_PTR));
    memcpy(m_err_msg, msg, len + 1);
}
